Braking



Aug. 16, 1938. vT. H. SCHOEPF ET AL 2,@27429 BRAKING Filed March l, 195'? 6 Sheets-Sheet l am E www Tm QM mm .jlwh 5MM..

)5%. m. mv Y BRAKING Filed March l, 1937 T. H. SCHOEFF ET AL Aug. 16, i938.

Aug. m 193g. T. H. SQHOEPF ET' M 1273429 BRAKING Filed March 17193'7V e sheets-shea@ e j 'l Il 1 M Il Il Il yll A TTONE YS Patented ug. 16, 1938 UNITED STATES PATENT OFFlCE BRAKING corporation of Ohio Application March 1, 1937, Serial No. 128,381

24 Claims.

This invention relates to braking mechanism and particularly to mechanism adapted automatically to control the intensity of application of the wheel and track brakes of a railway vehicle in such manner that the force of application of the respective brakes may be adjusted, during deceleration of the vehicle'under the influence of the brakes, in such manner as to compensate for increase of co-efcient of braking friction upon decrease in speed of the vehicle, in order to secure the utmost braking eiciency, while preventing the locking of the vehicle Wheels and the skidding thereof on the track rails during brake applications.

It is an object of this invention to provide means for simultaneously applying the wheel and track brakes of a railway vehicle and associated means responsive to the retardation of the vehicle for automatically simultaneously controlling the intensity of application of wheel and track brakes.

It is a further object of this invention to provide means of connection between vehicles in a railway train, whereby application of the wheel and track brakes of one vehicle will cause simultaneous application of the wheel and track brakes of all the vehicles and whereby the intensity of application of the wheel and track brakes of all connected vehicles will be controlled by the actuation of the control means on a single vehicle.

It is a further object of this invention to provide track trip actuated means for causing simultaneous application of the wheel and track brakes of the vehicle, and of all vehicles of the train, at maximum intensity which is thereafter adjusted by the control means in order to compensate for increase of co-eiiicient of braking friction during vehicle retardation.

It is a further object of this invention to provide means for manually causing simultaneous application of the wheel and track brakes of the vehicle at predetermined intensity which is thereafter automatically controlled by the control means to compensate for increase in co-eiiicient of braking friction due to retardation.

It is a further object of this invention to provide such manual means on one or more of the 'vehicles connected in a train whereby application of all the train brakes may be achieved by operation of a single manual means.

It is a further object of this invention to provide means responsive to parting of the train vehicles to cause automatic emergency application of all train brakes, both track and wheel.

It is a further object of this invention to provide manually operable means for making said last-named means inoperative during the removal of a vehicle from the train and subsequent shunting thereof. 5

It is a further object of this invention to provide, on one of the connected vehicles of a train, manual means, selectively operable to cause si multaneous application, either service or emergency, of the wheel and track brakes of all vehicles connected in the train.

It is a further object of this invention to provide, in such means, means for simultaneously controlling the intensity of application of the wheel and track brakes of a vehicle.

It is a further object of this invention to provide means for simultaneously controlling the intensity of application of all wheel and track brakes of all connected vehicles in a train.

It is a further object of this invention to provide such means for so controlling the wheel and track brakes that they are both applied at maximum intensity, and the intensity of application of both is thereafter simultaneously reduced at a rate proportional to the rate of retardation of the vehicle, or of the train.

It is a further object of this invention to provide such means for so controlling the wheel and track brakes that they are both applied at maximum intensity and the intensity of application 30 of both is then reduced at diierent rates, at least one of which is proportional to the rate of retardation of the vehicle, or of the train.

It is a further object of this invention to provide such meansk for so controlling the wheel 35 and track brakes that the wheel brakes are applied initially with maximum intensity and the track brakes with predetermined minimum intensity and the intensity of application of the wheel brakes is thereafter reduced concurrently 40 with increase of intensity of application of the track brakes, the rates of increase and decrease being proportional tothe rate of retardation of the vehicle, and/or train.

It is a further object of this invention to provide means for causing emergency application of both wheel and track brakes of a vehicle and/or train; by parting of a vehicle from another connected vehicle in the train; by actuav) tion of a track trip switch on a vehicle by a track trip mechanism; or manually, by manipulation of emergency brake applying means on the vehicle, the brake application being independent of the retardation responsive control means,

and the brakes of the vehicle and/or' train being applied at maximum intensity.

These and other objects and advantages will appear from the following description taken in connection with the drawings.

It is known that the co-eflicient of friction between the shoe of a friction wheel brake increases as the speed of the vehicle decreases under the inuence of the applied vehicle brakes.

Therefore, where the wheel brakes are initially applied at maximum intensity, it is desirable to thereafter decrease the intensity or force of application of the brake shoe to the wheel in order to prevent locking of the vehicle wheels and sliding thereof on the supporting track rails. According to the principles of this invention, this is accomplished by inertia responsive pendulum means which reduces the intensity or force of application of the wheel shoes to the wheels at a rate proportional to the rate of the above-explained increase of :zo-efficient of brake friction.

In addition, according to the principles of this invention, the track brakes are applied simultaneously with the application of the wheel brakes. The wheel brakes are initially applied at maximum intensity or with maximum force, while the track brakes are initially applied, either at maximum intensity or at predetermined minimum intensity, and the intensity of track brake application is thereafter either decreased or increased at a rate which is preferably proportional to the rate of decrease of intensity in wheel brake application, which latter rate is proportional to the rate of increase of co-efiicient of braking friction.

While it is desirable, in some cases, that both wheel and track brakes be initially applied at maximum intensity and the intensity of application thereof be simultaneously progressively diminished; in other cases, it is preferred that the wheel brakes be initially applied at maximum intensity and the intensity thereof be thereafter progressively decreased, while the track brakes are initially applied at predetermined minimum intensity and the intensity of application thereof be thereafter progressively increased simultaneously with the decrease of intensity of application of the wheel brakes. In this latter case, the utmost braking efficiency is achieved without sliding of the wheels on the tracks, because the track brakes, in their operation, are not susceptible to various factors which influence the wheel brakes because of the direct application 0f the track brakes to the track rails in` contrast to the application of the wheel brakes to the wheels of the vehicle, whereby the braking effect thereof is dependent upon the existence of traction between the vehicle wheels and the railway tracks.

By controlling the intensity of application of the wheel and track brakes in the above manner the track brakes in operation, draw the wheels down against the rail and thus increase traction between wheels and rail whereby the utmost braking efficiency is achieved as well as the utmost smoothness of operation of the vehicle or train during deceleration thereof upon application of the wheel and track brakes. During emergency brake applications, where smoothness and comfort must be sacrificed in the interest of safety, it 1s preferred that both wheel and track brakes be initially applied at maximum intensity and that the intensity of application thereof remain at its maximum value until the vehicle or train is brought to a stop.

Accordingly, we have provided means for accomplishment of the above objects and advantages, which means, along with their mode of operation, is hereinafter more clearly described.

In the drawings:

Figure 1 is a diagrammatic view illustrating the application of the principles of our invention to two vehicles of a train, and illustrating the means of connection between the respectiv-e mechanisms on the vehicles, different embodiments of our invention being shown as applied to the respective vehicles;

Figure 2 is a view similar to Figure l, but showing the application of other embodiments of our invention to two connected vehicles of a railway train;

Figure 3 is a view similar to Figure 2, but illustrating the application to two connected vehicles of a railway train other differing embodiments of our invention;

Figure 4 is an enlarged diagrammatic view similar to Figure 8, showing the application to a single vehicle of an embodiment of our invention similar to that embodiment illustrated at the right of Figure 3, but differing slightly therefrom;

Figure 5 is a View similar to Figure 4, showing the application to a single Vehicle of an embodiment of our invention broadly similar to that illustrated at the left of Figure 3, but varying slightly therefrom;

Figure 6 is an elevational view, partly in section, of a preferred type of biasing rheostat and combined actuating air engine and electrically controlled inlet and outlet valve devices;

Figure 7 is an elevational view, in section, of a preferred form of self-lapping electro-pneumatic valve device which is adapted to be controlled by the biasing rheostat illustrated in Figure 6 for controlling the flow of fluid to the wheel brake cylinder; and

Figure 8 is an elevational view, partly diagrammatic, illustrating a preferred form of retardation responsive control means for controlling the inlet and outlet Valves of the biasing rheostat actuating air engine illustrated in Figure 6.

Referring to the drawings in detail, with reference particularly to Figure l, the equipment of two cars or vehicles` of a railway train is illustrated, the equipment of the respective cars or vehicles being different in various details, as will hereinafter appear. In Figure 1, the wheel brake cylinders are designated I and are connected by means of pipe 2 to the self-lapping electro-pneumatic valve device 3. The source of fluid pressure comprising the reservoir 9 is connected by branch pipe 8 to the pipe line 4. The pipe line 4 is connected at one end to the self-lapping electropneumatic valve device 3 and at the other end to the supply valve 5 of the biasing rheostat operating air engine 'I. The air engine I is also provided with a release valve 6.

The air engine 'I is adapted to operate the biasing rheostat I0, the details of which air engine `I, supply valve 5, release valve 6 and biasing rheostat are illustrated in Figure 6 of the drawings. Each vehicle is provided with a suitable source of electric power I I, such as a storage battery, having the positive side thereof connected to the terminal I2 of the manually operable switch I3 which has the opposite terminal I 4 thereof connected to the train wire branch I5. The switch I3 is a two-point make type normally held open by a spring. The opposite side of the source of power II is connected by means of branch wire IB to the train wire branch I1 and by the branch wire I 8 to the wire I9 which is connected between terminals of the energizing solenoids of the valves 5 and 6. In the righthand vehicle shown in Figure 1, the train wire branch I5 is connected by means of wire 2U to one terminal of the solenoid 2 I, while the other terminal of the solenoid 2| is connected by means of wire 22 with the train wire branch I1,

The solenoid 2| cooperates with the armature 23 of a circuit closer having a switch plate 24 which is adapted, upon energization of the solenoid 2|, to engage and bridge the switch contacts 25 and 26. The switch contact 25 is connected by means of wire 21 with the wire 28 which is connected to the positive side of the source of power I The switch contact 26 is connected by means of wire 29 with one terminal of a resistance in the rheostat I0. The positive terminal of the source of power I I is also connected by means of wire 30 with the contact 3| of the retardation controller 32, the details of which are illustrated in Figure 8 of the drawings.

As shown in Figure 8, the retardation controller 32 is pivotally supported on a pin or the like 33 which is mounted on a suitable portion 34 of the vehicle, while the lower end thereof is provided with an enlarged and weighted head 35 to which is rigidly secured and insulated therefrom. the contact 3|. When the retardation controller swings to the left or in clockwise direction, as seen in Figure 8, it is adapted to cause engagement of the Contact 3| with the stationary contact 36 and the stationary contact 31, as will hereinafter more clearly appear. The stationary contact 36 is connected by means of wire 38 with a terminal of the solenoid of release valve 6, which solenoid has its other terminal connected to the cross wire I9. The stationary contact 31 is connected by means of wire 39 to one terminal of the solenoid of the supply valve 5, which solenoid has its other terminal connected to the cross wire Suitably connected to a terminal of the rheostat ID, opposite the terminal which is connected to the wire 29, is the wire 48 which is connected by means of the branch wire 4| to one terminal of the winding of the self -lapping electro-pneumatic valve device 3. The wire 4|] is also connected by means of wire 42 with one terminal of the coil 43 of the brake shoe 44, which brake shoe is supported by springs 45 sufficiently close to the rail 46 as to place the rail within its magnetic eld upon energization thereof. The terminal of the brake coil 43, which is opposite that terminal to which the wire 42 is connected, is connected by means of wire 41 to the wire 48 which is connected to the train wire branch I1. The wire 48 is also connected by means of wire 49 to that terminal of the winding of the valve device 3 which is opposite the terminal which is connected to the wire 4I.

The train wire branch I5 is connected by means of wire 58 with the contact 5I of the electric track trip switch 52. The wire 5|! is also connected by means of wire 54 with the trip contact 53. The wire 28 which is connected to the positive side of the source of power I I is also connected by means of wire 55 with the switch lever 56 of the electric track trip switch 52. Switch lever 56 of the track trip switch 52 is normally biased in neutral position, as shown in Figure 1, but is adapted to be engaged with either the contact 5| or the contact 53 upon engagement with the trip device 51. when it is properly set for engagement with the switch lever 56 of the electric track trip switch 52.

With reference to Figure 6, the position of parts of valves 5 and 6 of air engine 1 and rheostat l0 are shown in the position assumed by them when the switch I3 is open and the brake applying mechanism is de-energized. It will be seen that the pressure chamber 58 of the valve 5, which is always in communication with the fluid pressure in the pipe 4, is closed by the valve member 59 which, when the solenoid of the valve 5 is deenergized, is urged upwardly by the spring 60 in the pressure chamber 58, The valve 5 is provided with an intermediate chamber 6| which is connected by means of the branch 62 with the conduit 63 which leads to the left-hand end of the cylinder 64 of the air or fluid engine '1. Upon energization of the solenoid of the supply valve 5, the valve member 59 is urged downwardly against pressure of the spring 60 to provide communication between the pressure chamber 58 and intermediate chamber 6I, whereby fluid under pressure passes from the pipe 4 through pressure chamber 58 to intermediate chamber 6| and thus through branch 62 and conduit 63 to the lefthand end of the cylinder 64.

The pressure chamber 66 of the release valve 6 is connected by means of the branch 65 with the conduit 63. The valve member 61, during deenergization of the solenoid of the release valve 6, is urged upwardly by the spring 68 in the pressure chamber 66, whereby to provide communication from left-hand end of the cylinder 64, through conduit 63 and branch 65 to pressure chamber 66 and thence through intermediate chamber 59 and exhaust port 19 of the release valve 6 to the atmosphere. Thus, when the solenoids of the supply valve 5 and release Valve 6 are both de-energized, pressure from the pipe 4 prevented by valve member 59 from entering the intermediate chamber 6I of the supply valve 5, while at the same time pressure is released from the left side of the cylinder 64, whence it escapes through conduit 63, branch and chambers 66 and 69 of release valve 6,'through exhaust port 18 gization of the solenoid of the supply valve 5,

which causes fluid pressure to be introduced from the pipe 4 through the supply valve 5 to the lefthand end of cylinder 64. The means for accomplishing the energization of the respective solenoids has been described above and the operation thereof will be hereinafter described in detail. The lefthand end of the cylinder 64 is closed by a suitable cap 1|, while the righthand end is provided with flanges 12 and bearing boss 13 having therein a suitable aperture to slidably receive the piston rod 14 which is provided at its left end with a suitable fluid piston comprising metallic disks 15 and 16 having the resilient cup washer 11 clampingly secured therebetween. A compression spring 18 has one end in engagement with the disk 15 and the other end in engagement with the righthand end wall of the cylinder 64. This compression spring constantly urges the piston rod 14 toward the left. The above described parts comprise the rheostat operating fluid engine.

The rheostat comprises a cup-shaped casting 8|] suitably secured to the flanges 12 of the fluid engine and having at its right end the closure cap 8|. Suitably tapped resistance elements 82 and 83 are secured in the member 80 and are suitably insulated from the walls thereof. The taps of the resistance element 82 are connected to contacts 84 which extend radially inwardly. Opposite these contacts 84 are similar contacts 85 which are connected to the respective taps of the resistance element 83. Resistance elements 82 and 83 may be tapped at any suitable intervals which may be equal or unequal.

'I'he piston rod 14 is provided at its right end with a movable contact member 86 comprising an oppositely extending cylindrical member provided with suitable insulation 81 and having an end cap 88 at each end. The end caps are screwthreaded into the ends of the member 86 and are each provided with a central aperture having suitable insulation, which slidably receives contacts which are urged by the central compression spring 89. The uppermost contact which is adapted to engage the contacts 84 is designated 90, while the lower contact is designated 9|. Electrical connection between the contact 80 and contact 9| is provided by the spring 89.

In the position illustrated in Figure 6, the wire 29 is connected with the wire 40 through the leftmost contact 84, contact 90, spring 89, contact 8| and leftmost contact 85. No resistance is inserted between the wires 29 and 40 in this position of parts. When, however, pressure is introduced in the lefthand end of the cylinder 64, the piston rod 14 is moved to the right to engage the contacts 90 and 9| with other contacts 84 and 85, whereby to insert between the wires 29 and an amount of resistance depending upon `the resistance between the respective taps and depending also upon the excess of pressure in the lefthand end of the cylinder 64 over the pressure of the spring 18.

In the modified form of rheostat illustrated at the left sides of Figures 1 and 2, the piston rod 14 is provided with a pair of spaced members 86 and 86a which are identical and which cooperate in the same manner with contacts 84 and 85 and with contacts 84a and 85a respectively of the resistance elements 82, 83 and 82a, 83a` respectively, which resistance elements are placed in tandem. The resistance element 82a is similar to and in alignment with the resistance element 82, while the resistance element 83a. is likewise similar to and in alignment with the resistance element 83. The arrangement is such that, upon movement of the piston rod 14 to the right, the members 86 and 86a progressively bridge opposite contacts 84, 85 and 84a, 85a to insert diiering amounts of resistance between the wires connected to resistance elements 82, 83 and resistance elements 82a and 83a respectively.

In the arrangement illustrated at the left of Figure l, progressively increasing resistances are inserted between the wires connected to each of the rheostats I0 and |0a, which resistances are proportional to the pressure in the left end of cylinder 64. In the arrangement illustrated at the left in Figure 2, the connection of wiring is such that increasing pressure in the air engine 1 increases the resistance inserted between the wires connected to the rheostat I0, while decreasing the resistance inserted between the wires connected to the rheostat |0a.

The details of the self-lapping valve device 3 are shown in Figure 7. The valve device 3 is provided with a supply valve 92. which controls the ow of fluid under pressure from the reservoir 9 through pipe 4 and pipe 2 to the brake cylinder I. The supply valve 92 is urged toward seating position by the spring 93, and limitation of the downward movement thereof is accomplished by suitable adjustment of the adjusting screw 94. The upper end of the valve member 92 is tapered at 95 for engagement with a release yvalve seat 96 to control the release of fluid under pressure from the pipe 2 which is connected to the brake cylinder The upper part of the valve device 3 includes an electromagnet having a winding 91, referred to above, having one terminal connected to the wire 4| and the other terminal connected to the wire 49. This winding cooperates, when energized, to urge the core member 98 downwardly against pressure of the spring 99 which constantly urges it upwardly and which spring is opposed by the spring |00 which engages the collar |0| which is screw threaded on the core 98. The lower end oi the core member 98 is screw-threadedly secured to the cup member |02 which has the release valve seat 96 formed therein.

A diaphragm |03 is secured between the cup member |02 and the core member 98 at its cen tra] portion and has the outer annual edge portions thereof secured between portions of the casing of the valve device 3. The pipe 4 com` municates with the lower or pressure chamber M34, in which the spring 93 is disposed and which is adapted to communicate, when the Valve member 92 is in downward position, with the intermediate chamber I 05 of the valve device to which isconnected the pipe 2. The lower end of the core member 98 is provided with a chamber |08 which communicates through the axial port |01 with the exhaust chamber |08. The exhaust chamber is provided with a port |09 which provides constant communication between the exhaust chamber |08 and the atmosphere.

A passageway is provided through the cup member |02 from the release valve seat 96 to the chamber |06. The tension of the springs 93, 99 and |00 is such that, when the winding 91 is cle-energized, the parts of the valve device 3 are in the position illustrated in Figure 7. In this position, the valve device 3 provides means of, communication between the brake cylinder and pipe 2 to the atmosphere. Upon energization of the winding 91, the core 88 is urged downwardly to engage the release valve seat 96 with the tapered surface 95 of the valve member 92 to block off the chamber |06 from the chamber |05 and also cause the valve member 92 to be urged downwardly against pressure of spring 93 to provide means of communication from pipe 4 through chamber |04 and chamber |05 to the pipe 2 and brake cylinder The downward displacement of the core member 98 is proportional to the energization of the winding 91. The intensity of, energization of the winding 91 is controlled by means of the rheostat I0, by insertion of resistance in the energizing circuit of the winding 91.

When, through actuation of the rheostat l0, the amount of resistance in the circuit is increased, the downward displacement of the core member 98 is decreased and the fluid pressure in the brake cylinder is decreased, the pressure in the brake cylinder being thus controlled in inverse ratio with respect to the resistance inserted by the rheostat l0 between wires 29 and 40 connected thereto. By this means, the intensity of wheel brake application may be controlled, because reduction of the intensity of the energization of the Winding 91, through operation of the rheostat I0, will cause reduction of pressure in the brake cylinder Operation Figure 1, right-When the parts are in the position illustrated in Figure 1, the winding of the Valve device 3 is de-energized and the brake cylinder I communicates with the atmosphere. The coil 43 of the track brake 44 is also deenergized. If the manual switch I3 is closed, a circuit will be completed from one side of the source of power I| through switch I3, train wire branch I5, wire 20, through solenoid 2l, wire 22, train wire branch I1, and wire I6 to the opposite side of the source of. poWerI I. This will energze the solenoid 2 I, whereby to place the switch plate 24 in bridging engagement with the contacts 25 and 26. A circuit is then completed from one side of the source of power |I through wire 28, wire 21, contact 25, switch plate 24, contact 26, wire 29, through the resistances of rheostat ID to wire 40, through wire 4I to the winding of the valve device 3, and from the winding through wires 49 and 48 to train wire branch I1, and thence through train wire branch I1 and Wire I6 to the opposite side of the source of power II. This circuit causes energization of the winding of the valve device 3.

Simultaneously, a circuit is completed from energized wire 4I) to Wire 42, through brake coil 43 and wire 41 to energized wire 48, whereby to cause energization of the brake coil 43 simultaneously with the energization of the winding of the valve device 3. Due to the fact that the valves and 6 were originally de-energize-d, the piston rod 14 of the air engine is in its leftmost position, whereby the intensity of energization of the winding of valve device 3 is at its utmost value. The pressure supplied to the cylinder I is likewise most intense and the ultimate intensity of the energization of the brake coil 43 is likewise secured due to the fact that the rheostat IIJ inserts no resistance between the Wires 29 and 48.

One side of the source of power I I is connected by wire 30 to the contact 3| of the pendulum retardation controller 32, while the other side of the source of power is connected by wire I8 to the wire I9 which is connected to the coils of the respective valves 5 and 6. The opposite ter minal of. the coil of valve 5 is connected by means of wire 39 with the stationary contact 31, while the opposite terminal of the coil of valve 6 is connected by means of wire 38 with the stationary contact 36. Therefore, upon retardation of the vehicle due to application of the wheel brakes by the cylinder I and due to application and energization of the rail brake 44, the contact 3| of the controller 32 will engage the stationary contact 36 to complete a circuit between one side of. the source of power II through wire 30, contact 3|, contact 36, wire 38, to coil of the release valve 6, from the coil of the relief valve to Wire I8 to the opposite side of the source of power II. This closes the release valve 6.

Upon further movement of the controller 32, the contact 3|, which still engages the contact 36 and retains the release valve 5 closed, also engages the stationary contact 31. This engagement completes a further circuit from one side of the source of power II through wire 30, contact 3|, contact 31, wire 39, coil of valve 5, wire I3, and wire I8 to the opposite side of the source of power II. This opens the supply Valve 5, whereby to introduce fluid under pressure from the reservoir 9 through branch pipe 5 and pipe 4 to the cylinder of the air engine 1. This causes the insertion of resistance in the energizing circuit for the valve device 3 and for the coil 43 of the track brake 44.

The engagement of the contact 3| with the contact 31 will be intermittent whereby, upon increase of the rate of retardation of the vehicle, pressure in the cylinder of the air engine will increase to increase the amount of resistance inserted between the wires 23 and 4|) b-y the rheostat I0. The increase of resistance causes decrease of the intensity of energization of the winding of the valve device 3, whereby to effect intermittent release of uid pressure from the brake cylinder I, while at the same time gradually reducing the intensity of the energization of the brake coil 43. As a result, the vehicle will be brought smoothly to a stop without causing the Wheels of the vehicle to slide on the rails of the track.

The above operation was accomplished through the manual closing of the manual switch I3 which is suitably located on the vehicle. Emergency brake applying means is also provided for operation of the braking mechanism by a track trip device 51 when placed in operative position. When this device is placed in operative position, it is disposed inthe path of the switch lever 56 on the moving vehicle. Upon the passage of the lever 56 past the track trip 51, in either direction, the switch lever 56 will be thrown either to the left or to the right to engage either the conn tact 53 or contact 5| to connect the wires 56 and 55. This completes a circuit from one side of the source of power II through wire 28 and wire 55, through switch lever 56 to wire 58, through train wire branch I5, through wire 28, through solenoid 2|, wire 22, train wire branch I1 and wire I6 to the opposite side of the source of power |I. This causes energization of the solenoid 2| to cause operation of the circuit closer in such manner that the switch plate 24 will bridgingly engage the contacts 2'5 and 26 of the circuit closer to cause operation of the mechanism in the abovedescribed manner.

Attention is particularly directed to the fact that one side of the source of power is connected by means of the wire I6 to the train wire branch I1 and that, when the train wire branch I5 is connected in any manner whatsoever with the opposide side of the source of power II, a circuit is completed through wires and 22'to energize the solenoid 2| of the circuit closer. Upon energization of the solenoid 2|, the circuit closer causes operation of the mechanism.

In the form of our invention illustrated at the left of Figure 1, a rheostat Illa is provided in tandem with the rheostat II) for separate control of the intensity of energization of the coil 43 of the track brake 44 simultaneous with the control of the energization of the winding of the valve device 3. The rheostat Ia is provided with tap resistance elements 82ar and 83a in tandem with the tap resistances 82 and 83 of the rheostat II), and the resistance elements 82a'r and 83a have contacts 84a and 85a respectively attached to the taps of the resistance elements 32a and 33a. The piston rod 14 is extended and provided with a second contact member 86a similar to the contact member 86 and disposed with respect to the contacts 84a and 85a in the same manner as is the contact 86 disposed with respect to the contacts 84 and 85.

The left end tap of the resistance element 82a, is connected by means of wire 29a with the wire 29, while the lefthand tap of the resistance element 83a is connected directly to the wire 42 which leads to the coil 43 of the brake shoe 44.

The opposite terminal of the coil `43 is connected by means of wire 4'I with the wire 48 which leads to the train wire branch I'I. The wire 22 which is connected with one terminal of the solenoid 2| is also connected to the wire 48, as is also the Wire 49 which leads from one terminal oi the- Winding of the valve device 3, which winding has its other terminal connected by the wire 4D to the left end tap of the resistance element 83. The wire 29 is connected to the lefthand tap of the resistance element 82 in the same maner as in the construction described above. Manual closing of the manual switch I3 on the vehicle, to the left of Figure l, causes energization of the valve device 3 and of supply valve 5 and release valve 6 in the manner above described to cause application of the wheel brakes by cylinder I with initial maximum intensity followed by gradual decrease of the intensity of application, during deceleration, as described above. Simultaneously, the coil 43 of the track brake 44 is energized and the intensity of energization thereof is gradually decreased through operation of the lsolenoid lila by the rheostat air operating engine 'I by gradual insertion of increasing amounts of resistance between the wires 29a and 42 through operation of the rheostat Illa.

The values of resistances 82 and 83a may be varied to vary the initial intensity of energization of the track brake coil 43 and likewise the arrangement of the taps of these resistances may be also varied to secure variations in the rate of decrease of intensity of energization during operation of the rheostat Illa by the air engine For the purpose of achieving emergency operation of the braking mechanism from the track trip 5'|, a modied form` of track trip operated switch is provided which comprises the air engine III) having the cylinder IIIprovided with a piston H2 urged downwardly by spring IIB, which piston H2' is connected by means of the stem H4 with the switch plate I I5. The lower end of the cylinder I-II is connected by means of pipe I I6 with the cylindrical casing II 'I of the track trip valve. The casing II'I is also connected, by means of the pipe H8, with the pipe 4. The casing II'I is provided with a cylindrical rotor H9 which is `rotatable therein and which is provided with ports and I2I. `At one end, the rotor H9 is provided with the lever |25 which is rigidly secured thereto.

In the position shown in Figure 1, communication between the pipes H6 and H8 is prevented by the rotor I I9, but, however, upon rotation of the rotor H9 in clockwise direction through an arc of forty-five degrees, the ends of the pipes H6 and H8 will `be connected by the port |20. If the rotor H9 is rotated by the lever in counterclockwise direction through an arc of forty-five degrees, the ends of pipes I I6 and H8 will be connected by the port |24. Upon the connection of the pipes H6 and H8, fluid under pressure will flow from the pipe 4 through pipe I8 and one `of the ports and through pipe H6 to the cylinder III. When the pressure in the bottom of the cylinder III overbalances the force of the spring H3, the switch plate H5 is placed in engagement with contacts 5| and 53. The swinging movement of the lever |25 of the track trip valve is accomplished by engagement therewith of the track trip device 5`| when it is placed in operative position and when the vehicle carrying the track trip valve passes over the device 51 in either direction.

Upon engagement of the switch plate I I5 with contacts 5| and 53, a `circuit is completed from one side of the source of power II through wire 55, Contact 53, switch plate H5, contact 5I, wire 5I), train wire vbranch I5, wire 2D, solenoid 2|, wire 22, wire 48, train wire branch Il', and wire I6 to the other side of the source of power II. 'Ihis causes the switch plate 24 to be engaged with the contacts 25 and 26 to cause operation of the mechanism in the manner described above.

Connection of train wire branches into train linen-The train wire branches Il of the adiacent cars in the train are adapted to be connected by means of the branch connectors Ila, while similar connection of the train wire branches I5 by branch connectors I5@ is also provided. The respective train wire branches I'I, therefore, become, in effect, a single train wire and the train wire branches I5 likewise be come, in effect, a single train wire, extending the of the braking mechanism, as described above.

When the respective train wire branches II are connected by the branch connector I'Ia, and the ytrain wire branches I5 are `connected by the branch connectors I5ft, connection of any source of power II branches I`I and I5 will cause energization of the solenoid 2| not only of the one vehicle, but of each vehicle .having the branches Il connected by connector I'Ia and the branches I5 connected by the connector I5a. For instance, in Figure 1, the righthand manual switch I3 is closed, a circuit is completed from one side of the source of power II onthe right vehicle through the adjacent train branch I5, through wire 2li, solenoid 2|, wire 22, train wire branch II and wire I6 to the opposite side of the source of power II. A parallel circuit extending from the righthand train wire branch I5 through connector I5a, lefthand train wire branch I5, lefthand wire 20, lefthand solenoid 2|, lefthand wire 2, lefthand wire 48, lefthand train branch II, branch connector Ha. to the righthand train wire branch I'I is completed. Thus, upon closing any manual switch I3 on a vehicle of a train having its train wire branches connected by branch connectors, each circuit .closer in the train will be simultaneously operated to cause operation of the brak- 'ing .mechanism thereon. The actuation of the track trip switch on any vehicle will likewise connect the source .of power I I of that vehicle across the train wire branches I5 and I 'I of that vehicle, whereby to likewise cause simultaneous operation of the circuit closers to cause simultaneous operation of the braking mechanism of each vehicle in the train.

While the track brake illustrated in Figure l is of the type wherein the shoe 44 is suspended by springs 45 closely adjacent the rail 46, and whereby application is caused by energization of the coil 43 which has the rail 46 within the magnetic eld thereof, other types of brakes which are vnormally suspended above the rail at substantial distance therefrom and which are positioned closely adjacent thereto by means of either an air engine such as is illustrated in Figbetween any of the train wire :y

ure 2, or by lever mechanism operated by a solenoid connected in the brake coil energizing circuit as illustrated at the right oi" Figure 3 may be used.

In the embodiment of our invention shown at the right of Figure 2, the electrical connections are the same as those illustrated at the right of Figure 1, save that, instead of the electrical track trip switch 52, the air engine operated track trip switch, illustrated at the left of Figure 1, is substituted. Also, instead of the form of brake illustrated in Figure 1, the brake M illustrated at the right of Figure 2 is of the type which is normally supported a substantial distance from the rail and application thereof is secured by positioning the brake shoe 44 closely adjacent the rail by means of the supporting air engine apparatus 12S.

The air engine |28 is provided with a cylinder |2'i carrying a reciprocable piston |28 which is constantly urged upwardly therein by means of the spring |29. The piston |28 is connected to the top of the shoe 44 by means of the stem |30. The upper end of the cylinder |21 is connected by means of pipe itl with the pipe 2, the fluid pressure of which is controlled by the selflapping valve device 3. The self-lapping valve device 3 is controlled in the same manner as in the form illustrated at the right of Figure l, described above, the pressure in the cylinder l and the cylinder |21 being controlled by the intensity of energization of the winding of the valve device 3.

When the operating circuit is closed manually by operation of the manual switch |3 of anyoi the cars in the train having their train line branches l5 and l'l connected, as described above, the winding of the valve device 3 receives its maximum energization whereby to supply fluid under maximum pressure to the cylinders and i221. In order that the brake 44 be positioned for application, it is necessary that the pressure in the cylinder |21 exceed the force of the spring |26. The amount of excess pressure regulates the quickness of actuation of the air engine |26 to position the shoe 44 for application. Likewise, when the pressure in the cylinder |21 is reduced below the force of the spring |29, the spring will urge the brake shoe 44 upwardly. The excess in spring pressure over the air pressure in the cylinder |21 will regulate the upward pressure applied to the shoe 44 and, necessarily, the amount of reduction in the force oi application of the brake shoe 44, because this upward force will be exerted against the downward force due to energization.

Generally, the strength of the spring is merely such as to withdraw the brake from the rail when pressure is released in the cylinder |21, but it is contemplated that the strength of the spring may be so chosen that a substantial pressure in the cylinder |21 is required to overcome the force thereof and position the shoe for application. The necessity for building up a substantial pressure in the cylinder |21 will then, cause delay of application of the shoe to the rail after the operating circuit is closed.

As in the embodiment illustrated at the right of Figure 2, the intensity of energization of the coil 43 of the brake shoe is regulated by the rheostat lll' simultaneously with the regulation of the intensity of energization of the winding of the valve device 3.

In the embodiment of our invention illustrated at the left of Figure 2, the structure is similar to that illustrated to the left of Figure 1, a change in the connection of the wires 29a, and 42 to the solenoid |0a is, however, made. The wire 22a is connected to the righthand tap of the resistance element 82a, while the wire 29 is connected to the lefthand tap ofthe resistance element 82. The wire 42 is connected to the righthand tap of the resistance element 83a', While the wire 4|] is connected to the lefthand tap of the resistance element 83. Due to this connection, upon initial energization of the winding'of the valve device 3 and of the coil 43 of the brake, no resistance will be inserted between the wires 29 and 4B by the rheostat while the ultimate amount of resistance will be inserted between the wires 29a and 42 of the brake coil energizing circuit.

Movement of the piston rod 14 to the right by the air engine l, during operation, as described above, will Icause resistance to be progressively inserted in the energizing circuit of the winding of the valve device 3, while the resistance inserted between wires 29a and 42 of the brake energizing circuit will be progressively reduced. In other words, decrease of the intensity of energization of the valve device 3 is accompanied by simultaneous increase in the intensity of energization of the brake coil. Therefore, during deceleration of the vehicle equipped according to the embodiment of our invention illustrated at the left of Figure 2, the intensity of wheel brake application will be progressively reduced, while the intensity of track brake application will be progressively increased.

As the actuation of the solenoids I0 and |0ct is responsive to the rate of retardation of the vehicle, it will be understood that, when the rate of retardation'exceeds a predetermined value, the intensity of application of the wheelbrakes will be reduced in order to prevent wheel slippage, while at the same time the braking effect of the track brakes will be increased to exert a steadying effect on the vehicle and increase the wheel traction, by reason of the vertical component of the track braking force, exerted between the vehicle supported track brakes and the rails, to secure the ultimate smoothness in deceleration of the vehicle.

In Figures 3, 4 and 5, a substantially diierent arrangement is illustrated, and in these figures,

the vehicle equipment illustrated at the right of Figure 3 is similarly arranged to that of Figure 4, save that, in Figure 4, the double rheostat and connections shown at the left of Figure 2 are substituted for the single rheostat illustrated at the right of Figure 3. The double rheostat thus provides means for progressively increasing the intensity of energization of the brake coil, while simultaneously progressively decreasing the intensity of application of the wheel brakes after the simultaneous initial application of the wheel and track brakes, Likewise, in the arrangement illustrated in Figure 5, the double rheostat and connections illustrated at the left of Figure l. have been substituted for the single rheostat illustrated at the left of Figure 3. This substitution is made so that the intensity of applications oi wheel and track brakes may be decreased progre'ssively after the initial simultaneous application. The use of separate rheostats for controlling the wheel and track brakes provides means whereby the respective rates of such decrease may be varied.

In the arrangement shown at the right of Figure 3, the wire I9 which connects terminals of the solenoids of valves 5 and 6 is connected by means of the wire `|8 to one side of the source of `power Il. The opposite terminal of the valve 5 is `connected by wire 39 `to stationary contact .31. The opposite terminal of the valve 6 is connected by wire 38 to the contact 36. The contact 3| of thecontroller 32 is connected by wire 38 to the opposite side vof the source of power Therefore, when the contact 3| of the controller engages the contact 36, a circuit is completed from the source ofzpower I I through wire 38, contact 3|, contact 36 and wire 38 to solenoid of valve 6, thence through wire I9 and wire |8 to the source of power I I. When the contact 3| engages the contact 31, a circuit is completed from the source of power through wire 38, `contact 3|, contact 31, wire 39, solenoid of valve 5, wire I9, and Wire |8 to the source of power II. The fluid connections of the air engine 1, valves 5 and 6, reservoir 9, self-lapping valve device 3 and wheel brake cylinder I are the same as at the right of Figure 1, described above.

The circuit closer contact 26 is connected by the wire 29 with one terminal of the solenoid I8, while the other terminal of the solenoid I8 is connected to the wire 40 which leads to the wire 4| which is connected to one terminal of the winding of the self-lapping valve device 3. The circuit closer contact `25 is connected by the wire 21 to the wire 28 which leads to one side of the source of power Il.

The train `wire branches are designated |4I, |42, |43, |44, |45, |46and |41 respectively. Similar train wire branches are provided for the adjacent vehicle at the left of Figure 3. The respective train wire branches |4| are adapted to be connected by jumper I4Ia; the respective train wire branches |42 are adapted to be connected by the jumper |42a; the respective branches |43 are adapted to be connected by the jumper |43a and likewise the branches |44 are adapted for connection by jumper |44a; branches |45 by jumper |45a; branches |46 by jumper |46a, and branches |41 by jumper |41a. IIn the respective vehicles, each train wire branch |46 is connected by the wire |39 with the wire 39 which connects the stationary contact 31 with a terminal of the valve 5. Likewise, the train branch wire |41 is connected by the wire |38 with the Wire 38 which connects the controller contact 36 with a terminal of the valve 6. By this means, the controller circuits for the valves 5 and 6 of the respective cars are connected in parallel in such manner that energization of the solenoids of the valves 5 and 6 by the controller on one car to a predetermined intensity `will be accompanied by like energization of the valves 5 and 6 of the adjacent `car to a like intensity. By means of this connection, `actuation of each controller mechanism in a train enables the actuated ycontroller to control the biasing rheostat of all other vehicles in the trains.

The train wire branch |45 which may be designated the return branch is connected by wire I6 with the same terminal of the source of power which has the wire |8 connected thereto. The return branch |45 has the return wire 49 connected thereto and extending to one terminal of the winding oi the valve device 3; also connected to the return branch |45 is the wire 28 which leads from one terminal of the solenoid 2| which operates the switch plate 24 of the circuit closer. Adjacent the return branch |45 is the emergency branch |44 which is connected by the Wire |48 with 'the emergency contact |49 of the manual brake switch |58. The brake switch '|58 is provided with a lever |5| having thereon a handle |52 provided with a suitable contact which is connected by means of wire |53 with one side of the source of power II. Also connected to the emergency branch |44 is the wire 58 which leads from the contacts 5| and 53 of the electric track trip switch 52.

The lever 56 of the track trip switch 52 is connected by the wire 55 to the wire 28. The emergency branch |44 is connected by the wire |54 to one terminal of the solenoid |55 of the emergency circuit closer |56 which has the other termina] of the solenoid |55 connected by wire |51 to the wire 28 which leads to the return branch |45. Associated with the solenoid |55 of the emergency circuit closer |56 is the armature |59 carrying a switch plate I 58 which is adapted for engagement with contacts |60 and |62. 'I'he contact |60 is connected by wire I6| to the wire 55 and the contact |62 has a wire |63 connected thereto. The wire |63 is connected to the fixed resistance |64, which resistance is also connected to the wire |65 which is connected to the wire 42 which leads to the brake coil 43. leading from the brake coil 43 is connected by means of wire |66 with the wire 20 which leads to the return branch |45. Thus, if the lever 56 of the track trip switch 52 is engaged with either of contacts 5| or 53, a circuit is completed, which extends from the source of power through wire 28, wire 55, switch 52, wire 50, emergency branch |44, wire |54, solenoid |55, wire |51, wire 28, return branch '|45 and wire 6 to the other side of the source of power II.

Energization of the solenoid |55 of the emergency circuit closer |56 causes the switch plate |58 to engage the contacts |68 and |62 to complete a circuit extending from the source of power through wire contact |68, switch plate |58, contact |62, wire |63, resistance element |64, wire |65, wire 42, brake coil 43, wire 41, wire |66, wire 28, return branch 45 and wire I6 to the other side of the source of power the brake coil 43 independently of the operation of the rheostat I8. The last-named circuit will be completed whenever the solenoid |55 is energized and the energization of this solenoid |55 may also be accomplished by engaging the lever |5| of the manual brake switch |58 with the emergency contact |49.

Upon engagement of the lever |5| with the emergency switch contact |49, a circuit is completed, which extends from the source of power through wire |53, emergency contact |49, wire |48, emergency branch |44, wire |54, solenoid |55, wire |51, wire 28, a part of the return branch |45, and wire I6 to the other side of the source of power |I. Thus, immediately upon engagement of the lever 56 of the track trip switch 52 with either of the `contacts 5| or 53 or engagement of the lever |5| of the manual brake switch |58 with the emergency contact |49 thereof, the solenoid |55 is energized to operate the emergency circuit closer '|56 to cause energization of the contact brake coil 43 at ultimate intensity.

Where the track brake 44 is of the construction illustrated in Figure l, energization of the coil 43 automatically causes application of the shoe 44 to the rail 46. However, in the form of brake illustrated at the right of Figure 3 (and in Figure 4), the shoe 44 is suspended by the springs "45 in the same manner as in Figure 1. However, the springs The Wire 41 28, a part of wire 55, wire |6I,

This causes energization of 45 suspend the shoe 44 at 75 substantial distance from the rail 46, and for this reason, it is necessary to provide means for positioning the shoe more nearly adjacent the rail in order that energization thereof will cause application of the shoe 44 to the rail 46. This means comprises the lever |61 pivotally supported in any suitable manner at |68. The pivotal support of the lever |61 is at one end thereof and the other end thereof is provided with a suitable projection |69 which rests upon the top of the shoe 44.

Intermediate the ends of the lever |61 is the armature |10 which cooperates with the solenoid |1| in such manner that energization of the solenoid I1| will cause the lever |61 to be swung downwardly to properly position the shoe 44 closely adjacent the rail 46 in such manner thatthe rail will be disposed within. the magnetic field of the shoe. One terminal of the solenoid |1I is connected by the wire |12 to the wire 42, while the other terminal of the solenoid |1| is connected by the wire |13 to the wire 41, which wires 42 and 41 are a part of the energizing circuit for the track brake coil 43. The solenoid |1| is, therefore, connected in parallel with the track brake coil 43. Energization of the track brake coil 43 is, therefore, accompanied by simultaneous energization of the solenoid |1|. Therefore, upon closing of the emergency circuit closer |56, the brake coil 43 and solenoid |1| are simultaneously energized to ultimate intensity of application of the track brake shoe 44 to the rail 46. This emergency application of the track brake shoe is, as above explained, totally independent of the rheostat l0.

While energization of the solenoid |55 of lthe emergency circuit closer |56, as described above, causes immediate application of the track brake shoe 44 to the rail 46 which is energized at maximum intensity, the application of the track brake 44 to the rail 46 independently of the operation of the controller mechanism and the rheostat |0 is also accompanied by simultaneous emergency application of the wheel brakes at maximum intensity whenever the solenoid |55 of the emergency circuit controller |56 is energized to place the switch plate |58 in engagement with the contacts |60 and |62. This is accomplished by energizing the winding of the self-lapping valve de-` vice 3 to maximum intensity upon each energization of the solenoid |55 of the emergency circuit closer |56. The closing of the circuit closer |56 completes, for this purpose, a circuit which extends from one side of the source of power through wire 28, wire 55, wire |6|, contact |60, switch plate |58, contact |62, wire |63, xed resistance |64 and wire |14 to the wire 4| which leads to one terminal of the winding of the selflapping valve mechanism 3.

The circuit further extends through the winding of the valve device 3, through wire 49, through return branch |45, and wire i6 to the other side of the source of power As this latter circuit is completed, whenever the emergency circuit closer |56 is closed, the simultaneous application of wheel brakes and track brakes to maximum intensity is accomplished either when the lever 56 of the track trip switch 52 is engaged with either of the contacts 5| or 53, or when the lever |5| of the manual switch |56 is engaged with the emergency contact |49 thereof. Due to the connection of the branches |45 of the respective vehicles by the jumpers |4511 and the connection of the respective branches |44 by the jumpers |44a, emergency application of the brakes on one |44 is the service train wire branch |43 which may be designated the service branch. The service branch |43 is connected by the wire 22 to one terminal of the solenoid 2| of the circuit closer, which solenoid 2| has its opposite terminal connected by the wire 20 to the return branch |45, as described above. The service branch |43 is connected by the wire |16 to the service contact 515 of the manual brake switch |50. When the lever i5| of the manual brake switch |50 is engaged with the service contact |15, a circuit is completed which extends from one side of the source of power l through wire |53, service contact |15, wire |16, service branch |43, wire 22, solenoid 2| of the circuit closer, wire 20, return branch |45, and wire |6 to the opposite side of the source of power This closes the circuit closer by engagement of the switch plate 24 with the contacts 25 and 26.

When the circuit closer is closed by engagement of the switch plate 24 with contacts 25 and 26, a circuit is completed from one side of the source of power through wire 28, wire 21, contact 25, switch plate 24, contact 26, and wire 29 to the rhecstat |0 and thence through Wire 40 and wire 4| to the winding of the valve device 3 and thence from the winding of the valve device 3 through wire 40, return branch |45 and wire I6 to the other side of the source of power There is also completed a circuit which extends from the wire 4| through wire |14, wire |65, Wire 42, track brake coil 43, wire 41, wire |66, wire 20, return branch Q45 and wire |6 to the last-named side of the source of power. The latter or track brake energizing circuit is in parallel with the energizing circuit for the winding of the valve device 3. Therefore, upon closing the circuit closer through energization of the solenoid 2|, the wheel and track brakes are applied and controlled through operation of the controller device 32.

Due to the above described connections provided by wire |38 connected from the wire 38 to branch |41, and by connection of wire 39 by wire |39 to branch |46, and the connection of the respective branches |46 and |41 of the respective cars, such service application of brakes responsive to control of controller device 32 is accompanied by like service application of the brakes of the other vehicles connected in the train responsive to the control of the controller device 32 on the vehicle having its brakes applied by service operation of the manual brake switch |50. As hereinafter described, means other than the manual brake switch |50 may be utilized for achievement of the same purpose.

For the purpose of causing emergency application of the track and wheel brakes of the connected vehicles of a train upon accidental parting of the train, the train wire branches |4| and |42 are provided on each vehicle. The respective train wire branches |42 are connected by the jumpers |42a and the respective train wire branches |4| are connected by the jumpers |4|a. An end jumper |11 is provided for connecting the free ends of the branches |4| and |42 at the end of the train. Each vehicle is provided with a manually operable switch having one contact |8| thereof connected by the wire |82 to the train wire branch |4|. The other contact |83 of the switch |80 is connected by the wire |84 to the wire 28.

The train wire branch |42 is connected by lic wire |85 with one terminal of the solenoid The other terminal of this solenoid |86 is connected to the wire 20. The solenoid |86 is a part of the normally open relay switch |81 which 'has an armature |88 associated with the solenoid |99, which armature carries the switch plate |89. r)The relay switch |81 is also provided with contact |90 connected by wire |9| with wire 55 and with crvntact |92 connected by wire |93 to the wire |63 above the nxed resistance |54. Normally, when the switch |88 is closed, a circuit extends from one side oi' the source of power through wire 28, wire |84, switch |88, wire |82, branch |4l, end jumper |11, branch |42, wire |95, solenoid |86, wire 28, return branch |45, and wire IB to the other side of the source of power li. The solenoid |86 is then energized to retain the switch plato |89 out of engagement with the contacts |90 and |92. Upon interruption of this circuit, the switch plate |89 engages the contacts if?) and |92 to complete a circuit from one side ef the source of power through Wire 28, wire wire |9|, contact |99, switch plate |897 con tact |92, wire |93, resistance |64, wire |14, winding ol the Valve device 3, wire 49, return branch |45, and wire I9 to the opposite side of the source power In parallel with this circuit is also a circuit eX- tending from one side of the source of power il, through wire 28, wire 55, wire I9I, contact itil?, .rn plate |89, contact |92, wire |93, res tance |84, wire |85, wire 42, track brake coil wire 41, wire |86, wire 28, return branch |45, and wire |6 to the other side of the source of power l. Thus, upon closing of the relay switch |81, emergency application of the wheel and track brakes full intensity is caused. Due to the mection of the train wire branches |4| by the npers i4|a and the connection of the train wire branches |42 by the jumpers |42a and the connection of the right ends of the branches |4| and |42 by the end jumper |11, as shown in Figure the lefthand switch |88 is closed to complete the energizing circuits of the solenoids |86 of the relay switches |81 to retain the relay switches |81 open. Upon parting of the loop comprising the connected branches |4|, end jumper |11 and connected branches |42, the solcncids |86 will be immediately de-energized to cause emergency application at full intensity of track and wheel brakes on each vehicle.

Such emergency application of the brakes of the vehicles upon parting of this loop is, as may be understood, undesirable during shunting of the cars. For this purpose, means is provided for energizing' the solenoids |88 independently of the completeness of the loop circuit provided by the connected branches |4| and |42. This means comprises the manual switch |94 provided on each vehicle having one contact connected by wires |95 to the branch |42 and the other contact connected by the wire |98 to the wire 28. When this switch |94 is manually closed, a circuit is completed, which extends from one side of the source of power through wire 28, wire |96, switch |94, wire |95, train wire branch |42, wire |85, solenoid |86, wire 20, return branch |45, wire i6, to the other side of the source of power Il. This circuit retains the solenoid |86 energized whenever the switch |94 is manually closed. Thus, where, as shown in Figure 3, the vehicles are connected, the righthand vehicle may be disconnected by closing both switches |94 on the vehicle shown and inserting a jumper |11 at the right-hand end of the train wire branches |4| and |42 of the lefthand vehicle, shown in Figure then releasing the leithand switch |94, and closing the righthand switch |89 before releasing the righthand switch |94. When this is done, the loops are complete on the respective vehicles and the vehicle may be moved without operation of the brakes by this means, save upon destruction of the electrical continuity thereof within the vehicle itself.

The structure shown in Figure 4 is similar to that illustrated at the right of Figure 3, save for the substitution for the single rheostat i of the double rheostat construction and connections shown at the left of Figure 2. In the structure shown in Figure 4, the righthand section Illa ol` the rheostat has the wire 29a connected to the righthand tap of one resistance thereof and also to the wire 29, while the righthand tap or the other resistance thereof is connected directly to the wire |14. The other connections are the same as those illustrated at the right of Figure 3 and the operation is the same, save that, upon service application of the brakes, the wheel brakes are initially applied with ultimate intensity and the intensity of application is thereafter reduced, while the track brakes are initially applied at their minimum intensity and the intensity .'iereof progressively increased simultaneously with the progressive decrease of intensity of application oi' the wheel brakes. This will be clearly understood upon reference to the above description of the operation of the mechanism shown at the left of Figure 2.

The embodiment illustrated at the left of Figure 3 is broadly similar to that illustrated at the right of Figure 3, but, instead of the manual switch |58, we have provided a manually operable drum controller generally designated |91 and shown in developed form. Rotor |98 is provided with segments, generally designated |99, which are adapted, when the line S-S thereof is in alignment with the contacts |52 and |15, to connect these contacts to provide means of communication between one side of the source of power Il and the train wire branch |43, and also adapted, when the line E--E thereof is placed in alignment with the contacts |52 and |49, to provide connection therebetween in such manner as to electrically connect one side of the source of power and the train wire branch |44. The manual switch |94 is similar to that of a construction illustrated at the right of Figure 3 and is similarly connected. The connections of the controller circuit are the same as that illustrated at the right of Figure 3.

The wire 23 is connected by the wire |84 with one contact |83 of the switch |88 which has the other contact I8 thereof connected by 'the wire |82 to the train wire branch Ifl. The wire 28 is also connected by the wire 55 with the contact 53 of the air engine operated track trip switch which is similar to that of Figure 2. The other contact of the track trip switch is connected by the wire 50 to the train wire branch |44. The return branch |45 is connected by the wire I6 to one side of the source of power The wires and 208 connect the source of power to the Contact 25 of the circuit closer which has the other vContact 28 thereof connected by means of wire 29 with one tap of one resistance of the rheostat i8. The corresponding tap of the other resistance of the rheostat I0 is connected by wire 48 to wire 4| which leads to one terminal of the winding of the valve device 3. The other terminal of the winding of the valve device is connected by wire 49 with the wire 20 which leads to the return branch |45. The wire 40 is also connected by the wire 42a to the wire |65 below the fixed resistance |64. The wire |65 is also connected to the'wire 42 which is connected to one terminal of the coil 43 of the brake shoe 44. The opposite terminal of the coil 43 is connected by the wire 41 to the Wire 20 which, as described, leads to the return branch |45.

The contact |62 of the emergency circuit closer |56 is connected by means of wire |63 with the Xed resistance |64 and with the contact |92 of the relay switch |81. The contact |60 of the emergency circuit closer |56 is connected by means of wire |6| to the wire 20| which is connected to the wire 200. The contact |90 of the relay switch |81 is connected by means of wire |9I and wire 202 with the wire 20 I. One terminal of the rheostat 2| is connected to the wire 20 and the other is connected to the branch |43 by means of wire 22. One terminal of the solenoid |55 is connected by wire |51 to the wire 20 and the other is connected by means of wire |54 to the branch |44. One terminal of the solenoid |86 is connected to the wire 20 and the other terminal is connected by the wire |85 to the branch |42. The valve of the track trip switch is connected by means of pipe ||8 to the pipe 4 and the pipe ||8 is connected by means of pipe 203 with the lower chamber of the self-lapping valve device 3a which is similar to the valve device 3.

The pressure chamber of the valve device 3a is connected to pipe I3| which leads to the cylinder |21 of the air engine |26 which is similar to the air engine brake support means illustrated at the right of Figure 2 and which has the brake shoe 44 supported on the stem |30 thereof. One terminal of the winding of the valve device 3a is connected by the wire 264 to the wire 42 and the other terminal of the winding of the valve device 3a is connected by wire 205 to the wire 41. The energizing circuits of the winding of the valve device 3a and the coil 43 of the track brake are thus in parallel.

The intensity of energization of the winding of the valve 3a controls the flow of fluid into the cylinder |21 of the air engine |26 whereby to control the rate oi movement of the stern |30 which supports the shoe 44 upon completion of the energizing circuit of the coil 43 of the brake shoe 44. This controls the time required for application of the shoe 44 to the rail 46. Also, as will be readily understood, when the energized shoe 44, in moving downwardly under the iniluence of the air engine |26, reaches a position sufliciently adjacent the rail 46 to place the rail within the magnetic iield of the shoe, further downward movement, due to energization, is opposed by a force which is proportional to the pressure in the cylinder |21 because, where the magnetically created force is greater than the difference between the fluid force and spring force, the magnetic force tends to create a partial vacuum in the cylinder |21 which is relieved at a rate proportional to the iiow oi iluid through the valve device 3a which, of course, depends upon the degree of intensity of energization of the winding thereof which, in turn, is controlled by the rheostat I simultaneously with the control of the intensity of energization of the coil 43 oi the brake shoe 44. The valve device Sa., therefore, provides means for controlling the quickness of application of the brake shoe 44 to the rail 46, the rate of movement of the shoe being substantially directly proportional to the rate of flow of fluid through the valve device 3a. which, in turn, is dependent upon the degree of intensity of energization of the coil 43 of the brake shoe 44, which coil has its energizing circuit in parallel with the energizing circuit of the winding of the valve device 3a.

Upon emergency application of the brake through manual emergency operation of the controller |91 or through operation of the pneumatic track trip by the track trip device 51, the coil of the valve device 3a is energized to its ultimate intensity, whereby the flow therethrough of fluid to the cylinder |21 occurs at the ultimate rate and the ultimate quickness of application of the brake shoe 44 is thereby secured.

As above described, due to the connection, in the train, of the train wire branches |41 by the jumpers |41a and the connection of the respective branches |41 by means of wires |38 with the respective wires 38, and due to the connection, in the train, of the train branch wires |46 by the jumpers I46a and their connection by means of wire |39 with the wire 39 of the respective vehicles, the retardation controller device 32 of either car may control the rheostats of all. Also, as pointed out above, the solenoid |86 is normally energized to prevent completion of the circuit between relay switch terminals |90 and |92. Upon actuation of the track trip device to place the switch plate I I in engagement with the contacts 5I and 53, a circuit is completed from one side of the source of power II through wire 28, Wire 55, contact 53, switch plate ||5, contact 5| and wire 50, emergency branch |44, wire |54, solenoid |55, wire 20, return branch |45 and wire I6 to the other side of the source of power Il. This causes the switch plate |58 of the emergency circuit closer |56 to engage the contacts |66 and I 62. This completes a circuit from one side oi the source of power through wire 30, wire T206, wire 20|, wire |6I, contact |60, switch plate |56, contact |62, wire |63, resistance element |64, wire |65, wire 42, track brake coil 43, wire 41, wire 20, return branch |45, wire I6, to the opposite side oi the source of power I I.

A circuit for energizing the winding of the valve device 3 is also completed, which extends from the resistance element |64, through wire 42a, wire 4|, winding of the valve device 3 and wire 49 to energized wire` 20. A circuit is also completed from energized wire |65 through wire 204, winding of the valve device 3a and wire 205 to energized wire 26. The windings of the valve devices 3 and 3a and the coil 43 of the track brake are, therefore, energized to the ultimate degree of intensity. lThis emergency energization of the windings of the two valve devices and of the coil 43 of the track brake will occur each time the emergency circuit closer |56 is closed by energization of the solenoid |55 thereof. Therefore, upon actuation oi the controller |91 to place the line E-E in alignment with the contacts |52, |15 and |49, the segment |99 will electrically connect the Contact.x |52 and |49 to complete a circuit from one side of the source of power |I through wire |53, contact |52, segment |99, contact |46, wire |48, branch |44, wire |54, solenoid |55, wire 20, return branch |45 and wire' I6` to the other side of the source of power I I.

As above described, upon parting of the loop consisting of the connected train wire branches |4| and |42 and end jumper |11, the solenoid |66 will be deenergized to cause the switch plate |89 to electrically connect the contacts |90 and |92 of the relay .switch |81. This will cause completion of a circuit extending from one side of the source of power 'through wire wire 266, wire 20|, wire 262, contact |90, switch plate |39, contact |92, wire |23, resistance clement |64, wire |65, wire 42, brake coil 43, wire 4?, wire 20, return branch |45 and wire it to the opposite side of the source of power ii. The energizing circuits for the windings of the. valve devices 3 and 3o, which are in parallel with the energizing circuit of the brake coil 43, will be simultaneously energized and the energization of the windings of the valve devices 3 and 3o of the coil 43 of the track brake will be of ultimate intensity. Such last described emergency brake application may, at any time, be prevented by closing the manual switches |94 on the respective vehicles.

The brakes, both wheel and track of the respective vehicles, may likewise immediately released after such emergency application by manually closing the switch iSd on that vehicle because, upon such closing of the switch, a circuit for energizing the solenoid |86 will then be completed, which circuit extends from one side oi the Source of power through a portion of wire 28, through wire |96 and switch |94, through wire |95, through wire |42, wire |85, solenoid |86, wire 20, return branch |45, and wire I6 to the other side of the source oi power l l.

Service application of the structure illustrated at the left of Figure 3 is accomplished by so manually oper-ating the controller as to place the line S--S in substantial alignment with the contacts |52, |15 and |49. The segment |98 will electrically connect the contacts |52 and |15 to complete the service circuit which extends from one side oi the source of power il, through wire |53, Contact |52, segment |99, contact |75, wire |16, service branch |44, wire 22, solenoid 2|, wire 20, return branch |45 and wire i5 to the opposite side of the source of power ii, This encrgizes the solenoid 2| ol' the circuit closer to engage the switch plate 24 with the contacts 25 and 26 of the circuit closer, This completes circuit irom one side of the source of power through wire 30, wire 20u, Contact 25, switch plate 24, contact 26, wire 29, through rheostat IU, wire 4|), wire 4|, winding of the valve device 3, wire 49, wire 2U, return branch |45 and wire |6 to the other side of the source of power A circuit will also be completed from the energized wire 40 through wire 42u, wire |55, wire 42, track brake coil 43, wire 41, to energized wire 2|). This circuit is in parallel with the energizing circuit for the valve device 3. Likewise, a circuit will be completed from energized wire` 42 through wire Zilli, through winding of the valve device 3a and through wire EDE to energized wire 2G. Thus, the windings of the valve devices 3 and 3a and the coil 43 of the track brake will be initially energized to ultimate intensity, and the intensity of energization thereof will be thereafter controlled by the insertion of resistance between wires 29 and 4U by the rheostat ||l through operation oi the air engine which is controlied by the retardation controller device 32.

The structure illustrated in Figure 5 is similar to that illustrated in Figure 3, tho only difference being that rheostatsi0 and in tandem are substituted for the single rheostat i0 used to control the energization of the valve devices 3 and 3o and the intensity of energization or the coil 43 of the track brake. The details of the tandem rheostat illustrated in Figure 5 are the same as those illustrated at the left of Figure 2. The Wire 29 has one end thereof connected to the contact 26 of the circuit closer and the other end thereof connected to the lefthand tap of one resistance of the rheostat IU. The corresponding tap of the other resistance of the rheostat lil is connected to the wire 4U which leads to one terminal of the winding of the valve device 3. the other terminal of which winding is connected by the wire 49 to the Wire 2U. The wire 29o has one end thereof connected to the wire 29 and the other end thereoi connected to the leithand tap of one resistance of the rheostat ma. The corresponding tap of the other resistance of the rheostat |Da is connected by means of the wire 42a with the Wire below the resistance element |64. The values of the resistances oi the rheostats ID and Illa may be varied, as described above in the description of the structure illustrated at the left of Figure 1.

Upon manual actuation of the controller |91, as described above, to energize the solenoid 2| oi the circuit closer, a circuit will be completed from one side of the source of power I! through wire 3|), wire 206, contact 25, switch plate 24, contact 26, wire 29 to the lefthand tap of one resistance of the rheostat and thence through the rheostat to the corresponding tap of the other resistance of the rheostat I0, through wire 4D to one terminal of the winding of the valve device 3, through wire 49, wire 2l), return branch. |45 and wire I6 to the opposite side ol the source of power A second circuit extends from the energized wire 29, through wire 29a to one tap of one resistance of rheostat illu, through the rheostat Illa from the corresponding opposite tap, through wire 42a, through wire |65, wire 42, track brake coil 43, wire 4l, wire |56, to energized wire 2U. Simultaneously, a parallel circuit will be completed from the energized wire 42, through wire 204, through winding of the valve device 3a and through wire 265 to energized wire |66.

Upon movement ol' the piston rod 14 to the right under the control of the retardation controller device 32, resistance will be progressively inserted between wires 29 and flii and between wires 29a and 42a to diminish the intensity oi energization of valve devices 3 and 3a and the intensity of energization oi brake shoe 44. The rheostat li controls the intensity oi' application of the wheel brakes through variation in the intensity of energization of the winding of the valve device 3, while simultaneously the intensity of energization ci the brake coil 4? and the rate of flow through the valve device 3a to position the shoe is controlled by the rheostat lilo..

It is to be noted that, in all constructions wherein the xed resistance |54 is utilized, it is so disposed as not to be included in any energizing circuit which includes the rheostat l0 or where the tandem arrangement is used, the rheostat IG or the rheostat lila. The fixed resistance |64 is, however, so disposed as to be included in the emergency energizing circuit of the brake coil 43 as well as the emergency energizing circuit lor the valve device 3 and where two valve devices are used in the energizing circuits of each of the valve devices 3 vand 3a. The purpose of this fixed resistance |64 is to prevent damage to the windings of the valve devices and to the coil 43 due to the fact that, in the emergency circuits, no resistance of the rheostats is included.

Furthermore, it is contemplated that the value of the respective resistances in the train system may be varied for the sake of balance and in order to secure uniform application in the respective vehicles of the train. It is contemplated that, where desired, any suitable known Variable resistance element may be substituted for the fixed resistance |64, the adjustability of such resistance may be utilized for the purpose of balancing the emergency braking circuits of the respective cars, as described above.

It is, of course, to be understood that it is preferable that each of the vehicles in a train be uniformly equipped according to the principles of our invention. For instance, While we have illustrated in Figure l two embodiments of our invention as connected in a train, it is preferred, though not absolutely necessary, that each vehicle be identically equipped.

Likewise, while we have shown but one track brake in the equipment of each vehicle, it is, of course, to be understood that a plurality or such brakes will be provided for each vehicle, which practice is conventional.

Likewise, while we have illustrated and described two-wire circuits for the Various mechanisms, and while such tWo-we circuits are preferred in order to avoid conflict with conventional railroad signalling systems, it is contemplated that, where desired, single wire circuits may be substituted for the double wire circuits by the substitution for the return wires of the various circuits, suitably located grounds.

It is preferred by us, in the practice of our invention, to secure utmost rapidity of brake application responsive to any of the devices provided by us ior this purpose. It is, therefore, proposed that all electrical devices, means and circuits shall be designed and constructed to eliminate 0r minimize all electrostatic and electromagnetic induction. We, therefore, prefer to use double wire circuits and eliminate the necessity for grounds and/or track return circuits. We also propose to so design the armature and core of all the electromagnetic devices as to secure the quickest possible action, such result being preferably secured by the use of the magnetic shunt principle.

Furthermore, while it has recently become a tendency to deliberately add to the inductance of magnetic track brake shoes in order to delay the energization thereof, it is proposed by us to reduce the inductance of the track brake shoes to a minimum in order to secure the utmost rapidity of energization and application. It is further preferred by us that all wires and cables utilized in the electrical circuits be composed of suitably twisted line strands and that the circuits be grouped in pairs and suitably disposed.

In the constructions illustrated in Figures l and 2, the rheostats are operated to control the brakes, both during service and during emergency operation. Simultaneous emergency application of both wheel and track brakes of all connected cars is achieved by operation of the track trip switch on any one car. Simultaneous service application of both wheel and track brakes of all connected cars is achieved by operation of the manual switch I3 on any car. The track trip switches are either electrical (Figure l, right) or fluid engine operated (Figure l, left, Figure 2). The track brakes are positioned either by energization alone (Figure l, Figure 2 left), by air engine (Figure 2, right, Figure 3 left, Figure 5), or by a solenoid connected in the energizing circuit of the brake coil 43 (Figure 3 right, Figure 4).

In Figure 2 (right), the self-lapping valve device 3 controls the rate of movement in positioning the track brake.

In Figures l and 2 (left), energization of the winding of the self-lapping valve device 3 and of the track brake coil 43 is controlled by separate simultaneously operable rheostats having common air engine operating means.

In Figure l (left), intensity of application of both wheel and track brakes is progressively diminished by the retardation controller device 32.

'In Figure 2 (left), intensity of application of the wheel brakes is progressively decreased, while intensity of application of the track brakes is simultaneously progressively increased.

In Figures 3, 4 and 5, as in Figures l and 2, service application of the wheel and track brakes on one vehicle of the train is accompanied by service application ci the brakes on all vehicles of the train.

In Figures 3, 4 and 5, means (|46, |41, |46a, lilla) is provided for making the brake control means on all vehicles connected in a train responsive to the retardation controller device on one vehicle of the train.

Means (including the loop train wire Ml, |42, Mila, |42a, lll) for causing emergency application of all train brakes upon parting of vehicles of thc train is also provided.

Means (switches |34 and |88 on each car) for making the last-named means inoperative to cause brake application during switching and shunting of the train vehicles is also provided.

Emergency brake application at maximum intensity, independent of the control means, is achieved.

The emergency application of both Wheel and track brakes (independently of the retardation controller) is secured either by parting of the connection of vehicles connected by the loop train line, by operation of the track trip switch, or by manual operation of the switch |50 or controller |91.

Means is provided, Figure 3 left, Figure 5, for controlling the positioning of the track brake shoe in predetermined manner.

In Figure 3 left and Figure 5, the self-lapping valve device 3 controls the vintensity of application of the wheel brakes, the intensity of energization of the track brakes and the intensity of energization of the self-lapping valve device 3a which determines the rate of movement in positioning the track brakes, i. e. the time required for application of the track brakes after application of the wheel brakes. In other words, the rheostat I0 is under the control of retardation controller device 32; the valve device 3 and track brake energizing circuit are under the control of rheostat lll; the valve device 3a is under the control of the track brake energizing circuit; and the brake positioning means is under the control of the valve device 3a.

In the construction at the right of Figure 3, the single rheostat I0 controls the intensity of energization of the winding of the self-lapping valve device 3 and also the intensity of energization of the track brake coil 43 and of the solenoid In the construction of Figure 4, the rheostat l0 controls the intensity of energization of the self-lapping valve device 3, While the rheostat ia, controls the intensity of energization of the track brake coil 43 and the solenoid Hl. The circuits of the coil 43 and of the solenoid I'll are in parallel in each of the constructions of Figure 4 and Figure 3, right. While in Figure 5,

decrease in the intensity of energization of the valve device 3 is accompanied by decrease of intensity of energization of the valve device 3a, and of the track brake coil 43. In Figure 4, decrease in intensity of energization of the valve device 3 is accompanied by increase in intensity of energization of the track brake coil 43 and the solenoid I'H. It is, of course, to be understood that the wires 29a and 42a of Figure 5 may be attached to other taps of the resistances of the rheostat Illa, as in Figure 4, and that the wires 29a and |14 may be attached to other taps of the resistances of the rheostat lUa in the same manner as is followed in Figure 5.

It is to be particularly noted that the principles of our invention may be applied to various known constructions of braking mechanism, to which they are additive and that the cost of application of the principles of our invention to such known braking systems is by no means so great as where it is necessary to substantially modify the known braking systems and install complicated systems of air lines and complicated valve structures. A particular disadvantage of the use of such air lines and pneumatic control mechanism consists in the difliculty of providing satisfactory connection between the pneumatic conduits of adjacent vehicles in a train. Where such systems are used, the coupling and uncoupling or such lines is extremely difficult and requires a substantial amount of time, and the cost of such pneumatic conduits and connections is prohibitive. In addition to this, the connections between the conduits of the respective vehicles have but short life due to the necessary exibility of connection between the respective vehicles in the train, which causes great wear upon iiexible pneumatic connections.

By the utilization of the principles of our invention, the former necessity for manual adjustment of the intensity of brake application is entirely obviated, all control of the intensity of brake application being accomplished through the automatic operation of the retardation controller 32 which properly adjusts the intensity of brake application during deceleration of the vehicle or train in such manner that the force of brake application is progressively reduced at a rate proportional to the increase in co-eilicient of brake friction due to decrease of the speed of the Vehicle. This adjustment is accomplished in such manner as to totally avoid the locking of the vehicle wheels and consequent slippage between the wheels and the track. The intensity of energization of the track brakes, which are applied simultaneously with the wheel brakes at full intensity, is thereafter reduced at a rate proportional to the reduction of the intensity ol wheel brake application or applied after the application of the wheel brakes (Figure 5, Figure 3, left), or the wheel brakes may be initially applied at full intensity, which intensity is thereafter reduced; while the track brakes are applied either simultaneously with or after the application of the wheel brakes, While energized at low intensity which intensity is thereafter increased during decrease of the intensity of application of the wheel brakes.

Due to the fact that the track brakes are unaiiected by certain conditions of operation, which materially affect the operative characteristics of the wheel brakes, this latter mode of operation is, in some cases, preferable. The track brakes are less susceptible, in operation, to the effects of water, oil or ice on the rail than are the wheel brakes, and the track brakes operate directly upon the rails irrespective of the existence or non-existence of traction between the wheels and the rails, while the wheel brakes depend, for their braking erliciency, upon traction between the vehicle wheels and the rails.

Furthermore, the track brakes, upon application apply downward pressure to the Vehicle trucks to force the wheels against the rails whereby to increase traction therebetween and therefore increase, in this manner, the eiiiciency of wheel braking by decreasing slippage between wheels and rails.

It will be understood that the above-described structure is merely illustrative of the manner in which the principles of our invention may be utilized and that we desire to comprehend within our invention such modications as come within the scope of the claims and the invention.

Having thus fully described our invention, what we claim as new and desire to secure by Letters Patent is:

l. In a railway vehicle having Wheel brakes and track brakes, common means for first applying said wheel, brakes and then applying said track arakes at predetermined intensity, and means for progressively diminishing the intensity of wheel brake application and for simultaneously increasing the intensity of track brake applica.- tion at rates proportional to the rate of change in speed of the vehicle during deceleration thereof.

2. In a train comprising connected railway vehicles having wheel brakes and track brakes, means on each of said vehicles operable to simultaneously apply the wheel and track brakes of all vehicles in the train at predetermined inn tensity, and means on each vehicle operable to adjust the intensity of application oi all of said brakes at a rate proportional to the rate of retardation of the vehicle.

3. In a train comprising a plurality of connected railway vehicles having wheel brakes and track brakes, means on each vehicle operable to apply the wheel and track brakes of all vehicles at maximum intensity, and means including a gravity and inertia responsive controller device on each vehicle for automatically adjusting the intensity of application of said brakes progressively at a rate proportional to the rate of increase of co-eicient of braking friction during deceleration of said train.

4. In a train comprising connected railway vehicles having wheel brakes and track brakes, means on each vehicle for simultaneously applying the wheel and track brakes of all vehicles in the train at predetermined intensity, and means on one of said vehicles for automatically diminishing the intensity of wheel brake application and simultaneously increasing the intensity of track brake application on all said vehicles at rates proportional to the rate of change in the speed or" the vehicle during deceleration.

5. In a method of braking for railway vehicles having wheel and track brakes, applying the wheel brakes, applying the track brakes at a predetermined interval thereafter, and progressively diminishing the intensity of application of the wheel brakes while increasing the intensity of application of the track brakes at a rate proportional to the rate of increase of braking friction.

6. In a method of braking for railway vehicles having wheel and track brakes, applying a maximum intensity the wheel brakes, applying at 

